1. Field of the Invention
The present invention relates generally to a system for providing information between vehicles and a remote location and for providing traffic management and vehicle navigation information between a vehicle and the remote location, and more specifically to a system and method for calculating routes by a traffic management system.
2. Description of Related Art
Navigation systems for determining a route from a start point to a destination point are well known in the art. In addition, navigation systems having capabilities for determining the geographic position of a reference point are also well known in the art (e.g., a Global Positioning System (GPS) or a self-contained system having distance and bearing sensors). As an example, a commonly used navigation system allows a user (or driver) of a vehicle to enter a destination place into the navigation system. The navigation system then looks up an appropriate route from an original point (using its geographic positioning capabilities) to the destination point in a road' map database (e.g., the route may be a route having the shortest distance from the start point to the destination, one which would take the vehicle the least time, or some other route), and guides the user to the destination point along the searched route through a visual display or vocal guide.
In searching the appropriate route, some types of mobile navigation system use traffic information (e.g., position data on traffic jams; information on roads closed by accidents, construction, or maintenance; lane-regulated locations) delivered from a traffic information supplier in addition to using the road map database. Conventionally, however, known methods for providing and utilizing the above-described traffic information for navigation remain very inflexible, cumbersome, and inefficient. For example, one method uses a one-to-one communication system to individually send traffic information streams to a particular vehicle in an attempt to send vehicle specific data to the particular vehicle. A drawback with this method is that many vehicles require the same information. For example, several vehicles might require the same regional traffic information. This method, therefore, requires the transmittal of the same information several times to a plurality of vehicles, which results in a waste of precious bandwidth. As known in the art, wireless network bandwidth is extremely sensitive to network capacity.
In other methods, the same traffic information is transmitted to all vehicles. The drawback with these methods is that many vehicles are inundated with a large amount of unwanted traffic information. Users and/or navigation systems are required to sift through the redundant, superfluous, or otherwise unwanted information to pick out pertinent traffic information.
As a result, there remains a need for systems and methods that allow for the transmittal of vehicle-related traffic information from a remote location to a vehicle and that allow for the selective transmittal of vehicle related information from a vehicle to a remote location. Moreover, it is desired that the navigation system be provided with enough information to properly determine efficient routes without being inundated with redundant, useless, and/or superfluous information. There is also a need that the information be provided to a user in a useful, efficient, and easily understandable manner. Accordingly, it would be very desirable to provide a traffic management architecture that overcomes the above-described shortcomings of the prior art while retaining their advantages.